Spectroscopy measurements for determination of polymer particle size distribution

Polymer and copolymer emulsion lattices based on styrene and butyl-metacrylate monomers are commercially important for many paints, adhesives, and coatings applications. The latex properties depend strongly on the copolymer composition, and particle size distribution, which in turn is function of the preparation of the latex and on the formulation of the emulsion designed for the particular application. This paper describes the implementation of multiwavelength spectroscopy measurements for size and distribution of the latex emulsions. The quantitative interpretation of the transmission spectrum is performed in the portion where no absorption is present (300–820 nm) leading to reliable estimated of particle size populations in the range of 0.02–20 μm. Particle size and particle size distribution of polymers and copolymers as function of reaction time and emulsion formulation are found in agreement with Smith Ewart (case 2 kinetics). The possibility of obtaining information from a single multiwavelength measurement makes UV–Vis spectroscopy a powerful tool for characterization of dispersed systems.